Prior to my first sheep hunt I studied this question and got the following guidelines from the "Grand Slam Club" boys.
They suggested first that tipping is a personal thing and obviously the better off you are the more you can share.
General guideline was a total tip of 10% of the cost of the hunt, to be divided with the guide, packer, cook, wrangler, etc.
They suggested you didn't need to tip the outfitter, since he had already gotten his money.
The grey part is the outfitter is also the guide, so there is were the "personal" part comes in.
I followed that guideline on my hunt, giving most to the guide, and some to the wrangler. The cook was a Jack*^&% and even got in a fight with the wrangler one night and knocked over my gun.
I let him and the outfitter know about the incident and withheld compensation.
Best of Luck